Polymerizable quaternary ammonium salts are important monomers for the production of water-soluble cationic polymers. The cationic polymers have significant utility as flocculants and retention auxiliaries in manufacturing operations such as the production of paper.
Among the widely used cationic monomers are methacrylamidoalkyl-trialkylammonium chlorides such as methacrylamidopropyltrimethylammonium chloride, as described in U.S. Pat. Nos. 4,460,758; 4,461,884; 4,556,736; 4,590,249; and 4,608,425.
A quaternary ammonium salt such as methacrylamidopropyltrimethylammonium chloride or the corresponding ammonium sulfate derivative are synthesized by methylating N-(3-dimethylaminopropyl)methacrylamide with either methyl chloride or dimethyl sulfate. The production of these quaternary ammonium salts requires specialized facilities since both methyl chloride and dimethyl sulfate are highly toxic reagents. Also, the resultant polymerizable quaternary ammonium salts exhibit corrosive properties and require special handling and storage.
The present invention embodiments were developed to overcome the deficiencies of the commercial type of polymerizable quaternary ammonium salts. Pertinent technical literature with respect to the present invention is that relating to quaternary ammonium carbonates, such as disclosed in U.S. Pat. No. 2,635,100 and Bull. Chem. Soc. Jap., 42, 1948 (1969).
Accordingly, it is an object of this invention to provide a novel polymerizable quaternary ammonium salt which is synthesized from low toxicity reactants.
It is another object of this invention to provide a novel acrylamidoalkyl-trialkylammonium salt which is non-corrosive, and which can be copolymerized with acrylamide to form a copolymer with superior flocculation efficiency as compared to commercial flocculants.
Other objects and advantages of the present invention shall become apparent from the accompanying description and examples.